Emmet sounds pretty close to what you’re asking about. It has various shortcuts to make writing HTML elements more convenient. Look specifically at its “Wrap with Abbreviation” feature – it’s a few more keystrokes than your suggested keyboard shortcut for wrapping in strong tags, but it can be used for any kind of tag.

Is there out of the box support for wrapping html in a strong tag? Normally this is ‘cmd-b’ but mine opens up the fuzzy-finder instead. I tried installing atom-HTMLizer, which adds support, but it said it was incompatible with my version. Just wondering if it is my configuration at this point because this is hard to believe it is not set by default.